Brain Booster 80 – Logic PuzzleThere are five children in the Pentax family. Alvin’s sister Becky is younger than Conrad, who is older than Debbie. Debbie has one older brother and a younger sister but her youngest brother Eddy is not the “baby” of the family. In what order are the children from eldest to youngest. (Pencil and paper may be used).

AnswerConrad, Debbie, Alvin, Eddy, Becky

Conrad is older than Debbie who is older than Alvin and Eddy (Debbie has only one older brother). If Becky was older than Alvin and/or Eddy this would make Eddy (who is Debby’s youngest brother) the “baby” of the family. But he is not, so Eddy is older than Becky. Eddy is Debbie’s youngest brother, so Alvin is older than Eddy and therefore older than Becky.

1. Top tree leaf removed. 2. Nose line on left giraffe removed. 3. Shadow on lower left coconut removed. 4. Leaf vein below gecko removed. 5. Ear line on left giraffe removed. 6. Bottom spot on right giraffe coloured in. 7. Small leaf at right of tree coloured in. 8. Horn on right giraffe moved.9. Spot on left giraffe moved. 10. Branch on left side shorter. 11. Gecko’s tail is longer. 12. One of gecko’s eyes is missing.

At exactly 5 minutes and 27.34 seconds after 1pm the hour hand and the minutehand of a clock exactly coincide (i.e. the minute hand is over the hour hand).What time is it when the two hands next coincide?

Answer

02: 10: 54.68 pm

The two hands of the clock were, of course, coincident at 12 noon.They took 65 minutes and 27.3 seconds to coincide again at 01: 05: 27.3 pm.It will take them another 65 minutes and 27.3 seconds to next coincide.

Horace the clockmaker set these five clocks to the correct time before retiring for the night. When he checked them the next morning he noticed that three of the clocks had run erratically during the night.The other two clocks had run correctly on time but one of them had stopped sometime after midnight. Which clock is showing the correct time?

Answer

Clock D.

Consider clock B. The hour hand is pointing to 5 o’clock, but the minute hand is pointing to 8. The angle between the two hands is incorrect. The angles between the hour and minute hands of clocks C andE are also incorrect. Clocks A and D have correct angles between their hour and minute hands, but clock A shows an earlier time than clock D, therefore clock A must have stopped during the night.Clock D is showing the correct time.

Of the 100 people at a recent party, 90 spoke Spanish, 80 spoke Italian, and 75 spokeMandarin. At least how many spoke all three languages?

Answer

45

10 could not speak Spanish, 20 could not speak Italian, and 25 could not speak Mandarin. So there could have been 10 people who spoke none of those languages.However, that would maximize the number of people who could speak all three, and the problem asks at least how many speak all three.Therefore, we must assume that these 10, 20, and 25 people are all separate people. Having identified 55 each of whom is missing one language, the remaining 45 speak all three.

Each of the nine squares in the grid marked 1A to 3C should incorporate all of the items which are shown in the squares of the same letter and number, at the top left, respectively. For example, 2B should incorporate all of the symbols that are in squares 2 and B. however, one square is incorrect. Which one is it?

The following word picture puzzles are pictograms that include a hidden word or a common phrase. Your task is to decipher the rebus puzzles. For example, the hidden phrasein the first pictogram is “first aid”.

Both shapes are perfect circles.______________________________________________________________________________

Brain Booster 19 – Cakey Problem

How do you cut a cake into eight equal pieces with only three cuts?

Answer

Use two cuts to cut the cake into four equal pieces. Use your third cut to cut the four pieces in half horizontally (perpendicular to the first two cuts).______________________________________________________________________________

A blind beggar had a brother who died. What relation was the blind beggar to the brother who died?

Answer

“Brother” is not the answer.

This puzzle is very simply stated and yet stumps those who have not heard it before, because the listener tends to make an implicit assump­tion about gender — in this case that a blind beggar is a man.

The following word picture puzzles are pictograms that include a hidden word or a common phrase. Your task is to decipher the rebus puzzles. For example, the hidden phrasein the first pictogram is “first aid”.

A swimming pool has four taps. The first can fill the entire pool with water in two days, the second – in three days, the third – in four days, and the last one can fill the pool in 6 hours. How long will it take to fill the pool using all 4 taps together?

Answer

To fill the poll with the first tap, we need 48 hours. Therefore, the first tap will fill 1/48 of the pool each hour. The second tap fills 1/72 of the pool each hour, the third tap 1/96 and the fourth tap fills 1/6 of the pool each hour. If every tap was being used, we would fill (1/48) + (1/72) + (1/96) + (1/6) = 61/288 of the pool each hour. Therefore, it would take 288/61 hours to fill the pool, which is 4 hours 43 minutes and about 17 seconds.

The circumference of the Earth is approximately 40,000 km. If we made a circle of wire around the globe that is only 10 meters (0.01 km) longer than the circumference of the globe, could a flea, a mouse, or even a man creep under it?

Answer

Using the formula for the perimeter of a circle (2or), we can calculate the radius of the earth (let 2or = 40,000) and the radius when the circumference is 0.01 km longer (let 2or = 40,000.01). The different in radii is 1.6 metres, meaning that a man would be able to creep under the wire.

The following word picture puzzles are pictograms that include a hidden word or a common phrase. Your task is to decipher the rebus puzzles. For example, the hidden phrasein the first pictogram is “first aid”.

A man who lives on the tenth floor takes the elevator down to the first floor every morning and goes to work. In the evening, when he comes back; on a rainy day, or if there are other people in the elevator, he goes to his floor directly. Otherwise, he goes to the seventh floor and walks up three flights of stairs to his apartment. Can you explain why?

Answer

The man is of short stature. He can’t reach the upper elevator buttons, but he can ask people to push them for him. He can also push them with his umbrella.

Is there a mistake in the calculations below, or is it fair to say that 1 = 2?

Answer

You cannot introduce x into the second line. By doing so, a quadratic equation is created, which in this case has 2 solutions, x = 1 and x = 2. However, we were already told that x is equal to 2, which mean that x = 1 is not a possible solution. The second last line is incorrect as well. To get the last line, we need to divide both sides by (x – 2). If x = 2, then (x – 2) is equal to (2 – 2) = 0, and we are unable to divide by 0 (x/0 = undefined). So 1 does not equal 2!

Take the she-goat to the other side of the river. Go back to the market side of the river, collect the cabbage, and row to the home side of the river. Unload the cabbage and put the she-goat onto the boat. Row to the market side and let the she-goat off. Then load the wolf onto the boat and row to the home side of the river. Unload the wolf and row back to the market side, collect the she-goat and cross the river to the other side where the wolf and cabbage are waiting!______________________________________________________________________________

Brain Booster 2 – Logic Puzzle

Which of the circles labelled A, B, C, D or E will continue the sequence in the pyramid and replace the circle with the question mark?

Answer

Answer is E_____________________________________________________________________________

Brain Booster 1 – How Many F’s?

Count the number of times that the letter F appears in the following sentence:

“Finished files are the result of years of scientific study combined with the experience of years.”

How many F’s did you find?

Answer

How many F’s did you find?

Three?

Wrong, there are six!

FINISHED FILES ARE THE RESULT OF YEARS OF SCIENTIFIC STUDY COMBINED WITH THE EXPERIENCE OF YEARS

Almost everyone guesses three. It seems that the brain cannot correctly process the word “OF”. The letter F usually makes the “f” sound, like in “fox”. However, in the word “of”, it makes a “v” sound. Somehow, your brain overlooks the word “of” as it scans for the sound of “f”.

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